The Johnsons and the Kennedys are popularly thought to have shared a strong mutual dislike, but stacks of letters and a remarkable tape of Jacqueline Kennedy reminiscing show something very different —and more interesting

THE GREAT STRUGGLES of our century have all been followed by tides of revulsion: Americans decided we were mad to have entered World War I; Russia should have been our enemy in World War II; the United States started the Cold War. Now another such tide has risen in Europe, and it may be on its way here.